The invention relates to apparatus for electroplating the contact elements of encapsulated electronic components and their like; it relates, more particularly, to apparatus provided with a flexible, continuous, electrically conductive conveyor belt with edges configured to engage and hold such encapsulated electronic components and carry them through the treatment stations of the apparatus associated with the plating or treating process.
In the field of electronics it has been known for some time that it is advantageous to manufacture discrete or integrated circuit elements in such a manner that the active portions of such elements are encapsulated in a ceramic slip--which is subsequently fired--with only passive contact elements protruding through the ceramic sheath so formed. In general the contact elements for such employment are stamped from a panel of sheet metal and contain internal connectors to the active electronic components as well as the protruding contacts destined to allow the circuit element--or chip, in some cases--to be connected into the appropriate electronic network. In many instances the process of manufacture of the lead frame will provide a selvedge to which all, or most, of the protruding contact elements are still attached prior to the plating operation and serving as a stiffening and handling frame until trimmed away in a final manufacturing step.
The protruding contact elements of the encapsulated electronic components frequently require the deposition of a different metal than the alloy of the metal panel from which they are formed, so as to permit the ready interconnection of the contacts by means of soldering, or, in some cases, for the sake of corrosion protection or other purpose.
The most commonly used metallic coatings applied by means electrodeposition are tin--for facilitating soldering--and silver or gold--where the contacts are used in a frictional mode and it desirable to enhance contact conductance. Where the underlying contact elements are made from an iron-based alloy, it is frequently coated with a thin `flash` of copper before the application of the desired surfacing material.